Methods and apparatus for improving the identification of multiple NFC-A devices

ABSTRACT

Aspects disclosed herein relate to improving technology detection and collision resolution among multiple NFC devices using a NFC type-A RF technology. In one example, a communications device is equipped to determine that a first device sensing response message includes one or more collisions, identify a first remote NFC device of the plurality of remote NFC devices by performing collision resolution on the first device sensing response message, transmit a sleep request message to the first remote NFC device that prohibits the first remote NFC device from responding to a first device sensing request message and the first device sensing request message, receive a second device sensing response message that includes collisions among the plurality of remote NFC devices, and identify a second remote NFC device of the plurality of remote NFC devices by performing collision resolution on the second device sensing response message.

CLAIM OF PRIORITY UNDER 35 U.S.C. §119

The present Application for Patent claims priority to ProvisionalApplication No. 61/594,270 entitled “METHODS AND APPARATUS FOR IMPROVINGTHE IDENTIFICATION OF MULTIPLE NFC-A DEVICES” filed Feb. 2, 2012, andassigned to the assignee hereof and hereby expressly incorporated byreference herein.

BACKGROUND

The disclosed aspects relate generally to communications between and/orwithin devices and specifically to methods and systems for improvingtechnology detection and collision resolution among multiple near fieldcommunication (NFC) devices using a NFC type-A radio frequency (RF)technology.

Advances in technology have resulted in smaller and more powerfulpersonal computing devices. For example, there currently exist a varietyof portable personal computing devices, including wireless computingdevices, such as portable wireless telephones, personal digitalassistants (PDAs) and paging devices that are each small, lightweight,and can be easily carried by users. More specifically, the portablewireless telephones, for example, further include cellular telephonesthat communicate voice and data packets over wireless networks. Manysuch cellular telephones are being manufactured with relatively largeincreases in computing capabilities, and as such, are becomingtantamount to small personal computers and hand-held PDAs. Further, suchdevices are being manufactured to enable communications using a varietyof frequencies and applicable coverage areas, such as cellularcommunications, wireless local area network (WLAN) communications, NFC,etc.

The NFC Forum Activity specification defines a technology detectionprocedure to use when resolving multiple devices, tags, and cards thatuse NFC Type A (NFC-A) radio frequency (RF) technology. The processincludes performance of a logical loop that is executed multiple timesso as to differentiate each device in an operating volume. Further, theprocess includes a device sensing response (SENS_RES) to a devicesensing request poll command (SENS_REQ). For NFC-A RF technologies, thedevice sensing response may indicate to the polling device informationit may use to perform collision resolution. However, where there aremultiple remote NFC devices (e.g., readers/writers, tags, cards, peerdevices, etc.) in the operating volume, the device sensing responseitself may suffer from collisions. The NFC Forum Activity Specification,as currently written, has the polling device perform collisionresolution based on the originally received device sensing response.When the original device sensing response continues to be used for everyiteration through the collision resolution process, a single devicedetect request (e.g., SDD_REQ) and/or a device sensing request generatedin response to analysis of the received device sensing response can onlybe the best interpretation, by the polling device, of what combinationof devices caused the original device sensing response collisions. Insuch an aspect, the polling device may be unable to determine what hasbeen sensed if there are collisions in certain bytes of the SENS_RES. Assuch, the device sensing response used to remove ambiguity during thetechnology detection procedure is currently the response that may be themost ambiguous.

Thus, improved apparatus and methods for improving technology detectionamong multiple NFC-A devices may be desired.

SUMMARY

The following presents a summary of one or more aspects to provide abasic understanding of such aspects. This summary is not an extensiveoverview of all contemplated aspects, and is not intended to identifykey or critical elements of all aspects nor delineate the scope of anyor all aspects. Its purpose is to present some concepts of one or moreaspects form as a prelude to the more detailed description presentedlater.

In accordance with one or more embodiments and corresponding disclosurethereof, various aspects are described in connection with improvingtechnology detection and collision resolution among multiple NFC devicesusing a NFC type-A RF technology. In an example, a communications deviceis configured to determine that a first device sensing response messageincludes one or more collisions, identify a first remote NFC device ofthe plurality of remote NFC devices by performing collision resolutionon the first device sensing response message, transmit a sleep requestmessage to the first remote NFC device that prohibits the first remoteNFC device from responding to a first device sensing request message andthe first device sensing request message, receive a second devicesensing response message that includes collisions among the plurality ofremote NFC devices, and identify a second remote NFC device of theplurality of remote NFC devices by performing collision resolution onthe second device sensing response message.

According to related aspects, a method for improving technologydetection and collision resolution among multiple NFC devices using aNFC type-A RF technology is provided. The method can include determiningthat a first device sensing response message includes one or morecollisions among a plurality of remote NFC devices. Further, the methodcan include identifying a first remote NFC device of the plurality ofremote NFC devices by performing collision resolution on the firstdevice sensing response message. Further, the method can includetransmitting a sleep request message to the first remote NFC device thatprohibits the first remote NFC device from responding to a first devicesensing request message. Further, the method can include transmittingthe first device sensing request message. Further, the method caninclude receiving a second device sensing response message that includescollisions among the plurality of remote NFC devices. Moreover, themethod may include identifying a second remote NFC device of theplurality of remote NFC devices by performing collision resolution onthe second device sensing response message.

Another aspect relates to a communications apparatus enabled to improvetechnology detection and collision resolution among multiple NFC devicesusing a NFC type-A RF technology. The communications apparatus caninclude means for determining that a first device sensing responsemessage includes one or more collisions among a plurality of remote NFCdevices. Further, the communications apparatus can include means foridentifying a first remote NFC device of the plurality of remote NFCdevices by performing collision resolution on the first device sensingresponse message. Further, the communications apparatus can includemeans for transmitting a sleep request message to the first remote NFCdevice that prohibits the first remote NFC device from responding to afirst device sensing request message. Further, the communicationsapparatus can include means for transmitting the first device sensingrequest message. Further, the communications apparatus can include meansfor receiving a second device sensing response message that includescollisions among the plurality of remote NFC devices. Moreover, thecommunications apparatus can include means for identifying a secondremote NFC device of the plurality of remote NFC devices by performingcollision resolution on the second device sensing response message.

Another aspect relates to a communications apparatus. The apparatus caninclude a transceiver, a memory, a processor coupled to the memory, anda NFC technology detection module coupled to at least one of the memoryor processor. The NFC technology detection module may be configured todetermine that a first device sensing response message includes one ormore collisions among a plurality of remote NFC devices, identify afirst remote NFC device of the plurality of remote NFC devices byperforming collision resolution on the first device sensing responsemessage. Further, the transceiver may be configured to transmit a sleeprequest message to the first remote NFC device that prohibits the firstremote NFC device from responding to a first device sensing requestmessage, transmit the first device sensing request message, and receivea second device sensing response message that includes collisions amongthe plurality of remote NFC devices. Moreover, the NFC technologydetection module may further be configured to identify a second remoteNFC device of the plurality of remote NFC devices by performingcollision resolution on the second device sensing response message.

Still another aspect relates to a computer program product, which canhave a computer-readable medium including code for determining that afirst device sensing response message includes one or more collisionsamong a plurality of remote NFC devices. Further, the computer-readablemedium may include code for identifying a first remote NFC device of theplurality of remote NFC devices by performing collision resolution onthe first device sensing response message. Further, thecomputer-readable medium may include code for transmitting a sleeprequest message to the first remote NFC device that prohibits the firstremote NFC device from responding to a first device sensing requestmessage. Further, the computer-readable medium may include code fortransmitting the first device sensing request message. Further, thecomputer-readable medium may include code for receiving a second devicesensing response message that includes collisions among a plurality ofremote NFC devices that does not include the first remote NFC device.Moreover, the computer-readable medium can include code for identifyinga second remote NFC device of the plurality of remote NFC devices byperforming collision resolution on the second device sensing responsemessage.

To the accomplishment of the foregoing and related ends, the one or moreaspects comprise features hereinafter fully described and particularlypointed out in the claims. The following description and the annexeddrawings set forth in detail certain illustrative features of the one ormore aspects. These features are indicative, however, of but a few ofthe various ways in which the principles of various aspects may beemployed, and this description is intended to include all such aspectsand their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed aspects will hereinafter be described in conjunction withthe appended drawings, provided to illustrate and not to limit thedisclosed aspects, wherein like designations denote like elements, andin which:

FIG. 1 is a block diagram of a wireless communication system, accordingto an aspect;

FIG. 2 is a schematic diagram of a wireless communication system,according to an aspect;

FIG. 3 is a block diagram of a NFC environment, according to an aspect;

FIG. 4 is a flowchart describing an example of improving technologydetection among multiple NFC-A devices, according to an aspect;

FIG. 5 is a flowchart describing another example of improving technologydetection among multiple NFC-A devices, according to an aspect;

FIG. 6 is a functional block diagram of an example architecture of acommunications device, according to an aspect; and

FIG. 7 is a functional block diagram of an example communication systemfor improving technology detection among multiple NFC-A devices,according to an aspect.

DETAILED DESCRIPTION

Various aspects are now described with reference to the drawings. In thefollowing description, for purposes of explanation, numerous specificdetails are set forth to provide a thorough understanding of one or moreaspects. It should be understood, however, that such aspect(s) may bepracticed without these specific details.

Generally, during a technology detection procedure a polling device mayreceive device sensing responses from multiple remote NFC devices withinan operating volume that collide with each other. A collision resolutionloop may be used to attempt to identify each remote NFC device thatprovided a device sensing response. The collision resolution process maycontinue until each of the multiple remote NFC devices has beenseparately identified. During each iteration of the collision resolutionloop, each resolved NFC device may be placed in a sleep mode, a newdevice sensing request may be sent by the polling device, and new devicesensing responses may be received from any unresolved and awake NFCdevices. The newly received device sensing response may include fewercollisions than the previously received device sensing response becausethe NFC devices in sleep mode do not provide a device sensing response.The collision resolution loop may continue using the newly receiveddevice sensing response during each collision resolution loop iterationuntil no additional collisions are detected.

FIG. 1 illustrates a wireless communication system 100, in accordancewith various exemplary embodiments of the present invention. Input power102 is provided to a transmitter 104 for generating a radiated field 106for providing energy transfer. A receiver 108 couples to the radiatedfield 106 and generates an output power 110 for storing or consumptionby a device (not shown) coupled to the output power 110. Both thetransmitter 104 and the receiver 108 are separated by a distance 112. Inan exemplary embodiment, transmitter 104 and receiver 108 are configuredaccording to a mutual resonant relationship and when the resonantfrequency of receiver 108 and the resonant frequency of transmitter 104are very close, transmission losses between the transmitter 104 and thereceiver 108 are minimal when the receiver 108 is located in the“near-field” of the radiated field 106.

Transmitter 104 further includes a transmit antenna 114 for providing ameans for energy transmission. A receiver 108 includes a receive antenna118 as a means for energy reception. The transmit and receive antennasare sized according to applications and devices associated therewith. Asstated, an efficient energy transfer occurs by coupling a large portionof the energy in the near-field of the transmitting antenna to areceiving antenna rather than propagating most of the energy in anelectromagnetic wave to the far field. When in this near-field acoupling mode may be developed between the transmit antenna 114 and thereceive antenna 118. The area around the antennas 114 and 118 where thisnear-field coupling may occur is referred to herein as a coupling-moderegion.

FIG. 2 is a schematic diagram of an example near field wirelesscommunication system. The transmitter 204 includes an oscillator 222, apower amplifier 224 and a filter and matching circuit 226. Theoscillator is configured to generate a signal at a desired frequency,which may be adjusted in response to adjustment signal 223. Theoscillator signal may be amplified by the power amplifier 224 with anamplification amount responsive to control signal 225. The filter andmatching circuit 226 may be included to filter out harmonics or otherunwanted frequencies and match the impedance of the transmitter 204 tothe transmit antenna 214.

The receiver 208 may include a matching circuit 232 and a rectifier andswitching circuit 234 to generate a DC power output to charge a battery236 as shown in FIG. 2 or power a device coupled to the receiver (notshown). The matching circuit 232 may be included to match the impedanceof the receiver 208 to the receive antenna 218. The receiver 208 andtransmitter 204 may communicate on a separate communication channel 219(e.g., Bluetooth, Zigbee, cellular, etc).

With reference to FIG. 3, a block diagram of a communication network 300according to an aspect is illustrated. Communication network 300 mayinclude communications devices 310 which, through antenna 324, may bewithin an operating volume of two or more remote NFC devices (330 a, 330b, 330 n). Each NFC device (310, 330 a, 330 b, 330 n) in thecommunication network 300 may use one or more NFC RF technologies 326(e.g., NFC-A, NFC-B, NFC-F, etc.). In an aspect, communications device310 may use NFC technology detection module 350 to poll the operatingvolume to attempt to detect the presence of and identify each of theremote NFC devices (330 a, 330 b, 330 n). Each remote NFC device (330 a,330 b, 330 n) may be configured to respond with a device sensingresponse message (338 a, 338 b, 338 n) to the communications device 310polling using NFC technology response module 332 through one or more RFinterfaces 334 using one or more RF protocols 336. In an aspect, each ofthe remote NFC devices is configured to use a NFC-A RF technology whentransmitting the device sensing response messages (338 a, 338 b, 338 n).In another aspect, communications device 310 may be configured to beconnected to an access network and/or core network (e.g., a CDMAnetwork, a GPRS network, a UMTS network, and other types of wireline andwireless communication networks). In an aspect, remote NFC devices (330a, 330 b, 330 n) may include but are not limited to a remote NFC tag, areader/writer device, a peer initiator device, a remote peer targetdevice, etc.

Communications device 310 may include NCI 320. In an aspect, NCI 320 maybe configured to enable communications between a NFC enabled antenna 324and NFC controller 312.

Communications device 310 may include a NFC controller (NFCC) 312. In anaspect, NFCC 312 may include RF discovery module 314. RF discoverymodule 314 may be configured to perform RF discovery using a discoveryprocess. One aspect of the discovery process may include polling for thepresence of one or more remote NFC devices (330 a, 330 b, 330 n)configured to communicate using a NFC-A RF technology. DH 340 may beconfigured to generate a command to prompt NFCC 312 to perform variousfunctions associated with RF discovery.

Communications device 310 may include NFC technology detection module350. NFC technology detection module 350 may be configured to generateand communicate a device sensing request message 352. In an aspect, thedevice sensing request message 352 may be a SENS_REQ message as definedin the NFC Forum Digital Protocol specification. NFC technologydetection module 350 may receive one or more device sensing responsemessages (338 a, 338 b, 338 n) from one or more remote NFC devices (330a, 330 b, 330 n) resulting in a received device sensing response thatincludes one or more collisions 354. In an aspect, each device sensingresponse message (338 a, 338 b, 338 n) may be a SENS_RES message asdefined in the NFC Forum Digital Protocol specification. NFC technologydetection module 350 may further include collision resolution module 356that may be configured to analyze the received device sensing responsethat includes one or more collisions 354. Although FIG. 3 depicts NFCtechnology detection module 350 is a separate module, one of ordinaryskill in the art would appreciate that the functionality associated withNFC technology detection module 350 may be included within one or morecomponents, such as but not limited to, NFCC 312, DH 340, etc.

Communications device 310 may include further include memory 360 thatmay be configured to store one or more parameters received in the one ormore received device sensing response that include one or morecollisions 354. In another aspect, each newly received device sensingresponse 354 may be stored in memory 360 by writing over and/or deletinga previously stored device sensing response 354.

In one operational aspect, collision resolution module 356 may identifyone (e.g., 330 a) of the multiple remote NFC devices (330 a, 330 b, 330n) and communications device 310 may transmit a sleep request to theidentified remote NFC device (e.g., 330 a). In an aspect, the devicesleep request message may be a SLP_REQ message as defined in the NFCForum Digital Protocol specification. Thereafter, NFC technologydetection module 350 may transmit another device sensing requestmessage. As one of the multiple remote NFC devices was prompted into asleep mode by the sleep request message, a subsequently received devicesensing response 354 may include no more collisions than a previouslyreceived device sensing response, and may include fewer collisions 354.Thereafter, collision resolution module 356 may use the subsequentlyreceived device sensing response 354 to perform collision resolution. Inother words, each time through the NFC collision resolution loop, theremay be one fewer device sensing response for a remote NFC device (330 a,330 b, 330 n) (e.g., peer device, reader, writer, tag, card, etc.) thatresponds to the device sense request message 352. As such, the mostrecently received device sensing response 354 is at least no worse thanany previously received device sensing responses 354, and in fact, maybe better because it may include fewer collisions and less ambiguityeach iteration. Continuing the operational aspect described above, onthe final iteration through the NFC collision resolution loop, becauseonly one remote NFC device (e.g., 330 n) may be awake to respond, thefinal device sensing response message 354 may be collision free.

Therefore, a system and method is disclosed to provide improvedtechnology detection for communications device 310 with multiple remoteNFC devices 330 a, 330 b, 330 n.

FIGS. 4-5 illustrate various methodologies in accordance with variousaspects of the presented subject matter. While, for purposes ofsimplicity of explanation, the methodologies are shown and described asa series of acts or sequence steps, it is to be understood andappreciated that the claimed subject matter is not limited by the orderof acts, as some acts may occur in different orders and/or concurrentlywith other acts from that shown and described herein. For example, thoseskilled in the art will understand and appreciate that a methodologycould alternatively be represented as a series of interrelated states orevents, such as in a state diagram. Moreover, not all illustrated actsmay be required to implement a methodology in accordance with theclaimed subject matter. Additionally, it should be further appreciatedthat the methodologies disclosed hereinafter and throughout thisspecification are capable of being stored on an article of manufactureto facilitate transporting and transferring such methodologies tocomputers. The term article of manufacture, as used herein, is intendedto encompass a computer program accessible from any computer-readabledevice, carrier, or media.

FIG. 4 depicts an example flowchart describing a process 400 forimproving NFC technology detection in a communications environment inwhich multiple remote NFC devices are present.

At block 402, a NFC device may determine that a first device sensingresponse message includes one or more collisions among a plurality ofremote NFC devices. In an aspect, the first device sensing response maybe obtained by transmitting a device sensing request message as part ofa technology detection process, and receiving the first device sensingresponse message in response to the first device sensing requestmessage. In an aspect, the first device sensing response by be stored bythe NFC device. In an aspect, each of the plurality of remote NFCdevices is configured to use NFC-A radio RF technology. In anotheraspect, the plurality of remote NFC devices may include any combinationof a reader device, a writer device, a tag, a card, and a peer device,etc.

At block 404, the NFC device may identify a first remote NFC device ofthe plurality of remote NFC devices by performing collision resolutionon the first device sensing response message. As used herein, a firstremote NFC device merely refers to one of the multiple remote NFCdevices that have been identified. One of ordinary skill in the art willappreciate that application of a “first” label only occurs in thecontext of identification of a remote NFC device and does not correspondto any ordering, ranking, and/or characterizing the multiple remote NFCdevices. In an aspect, single device detection communications, used aspart of technology detection, may include a NFCID that may identify eachremote NFC device.

At block 406, the NFC device may transmit a sleep request message to thefirst remote NFC device that prohibits the first remote NFC device fromresponding to a first device sensing request message. In an aspect, thesleep request message includes a SLP_REQ message as defined in the NFCForum Digital Protocol specification.

At block 408, the NFC device may transmit the first device sensingrequest message. In an aspect, the first device sensing request messageincludes a SENS_REQ message as defined in the NFC Forum Digital Protocolspecification.

At block 410, the NFC device may receive a second device sensingresponse message that includes collisions among the plurality of remoteNFC devices. In an aspect, the first and second device sensing responsemessages may be SENS_RES messages as defined in the NFC Forum DigitalProtocol specification. In an aspect, the second device sensing responsemessage may be stored on the NFC device. In one such aspect, the seconddevice sensing response message may be stored so as to overwrite thefirst device sensing response message. In another aspect, the seconddevice sensing response message may be stored with the first devicesensing response message. Further, subsequent device sensing responsemessage may be stored with the first and second device sensing responsemessage and the NFC device may analyze the stored messages to identifyor more other remote NFC devices of the plurality of remote NFC devices.

At block 412, the NFC device may identify a second remote NFC device ofthe plurality of remote NFC devices by performing collision resolutionon the second device sensing response message. As noted above withrespect to the use of “first,” “second” as used herein merely refers toanother one of the multiple remote NFC devices that have beenidentified. One of ordinary skill in the art will appreciate thatapplication of a “second” label only occurs in the context ofidentification of a remote NFC device and does not correspond to anyordering, ranking, and/or characterizing the multiple remote NFCdevices.

FIG. 5 depicts an example flowchart describing another process 500 forimproving RF discovery for peer mode passive communications.

At block 502, a NFC device may send a device sensing request (e.g.,SENS_REQ) as part of a technology detection process. As used herein, thetechnology detection process assists the NFC device in detecting andidentifying one or more remote NFC devices within an operating volume ofthe NFC device.

At block 504, the NFC device may receive an initial device sensingresponse (e.g., SENS_RES) that includes one or more collisions. As usedherein, a collision refers to an indication in the message that multipleremote NFC devices have responded in such a manner as to result in botha “0” and a “1” bit be received for a single value. In other words, oneremote NFC device may include a “0” at a location within its NFCID whileanother remote NFC device may include a “1” at the same location withinits own NFCID.

At block 506, the NFC device may store the received initial devicesensing response. In aspect, the NFC device may store received devicesensing responses on non-volatile (NV) memory available on a NFCcontroller. In another aspect, the NFC device may store received devicesensing responses on memory (e.g., memory 608) available in the NFCdevice.

At block 508, the NFC device may perform collision resolution toidentify one of the devices that sent a device sensing response.

At block 510, the NFC device determines whether there are any collisionsremaining in the most recently analyzed device sensing response. If atblock 510, the NFC device determines that no collisions remain pending,then at block 512, the collision resolution process may successfullyterminate.

By contrast, if at block 510, the NFC device determines that one or morecollisions remain pending, then at block 514, the NFC device may send asleep request to the remote NFC device identified through the mostrecent collision resolution.

At block 516, the NFC device may send a device sensing request toattempt to detect and identify one or more remote NFC devices thatremain unidentified in the operating volume.

At block 518, the NFC device may receive a subsequent device sensingresponse. As used herein, a subsequent device sensing response mayinclude any device sensing device that is received after the initialdevice sensing response has been received.

At block 520, the NFC device may store the subsequently received devicesensing response. In an aspect, each subsequently received devicesensing response may be saved so as to overwrite a previously saveddevice sensing response. In another aspect, each of the received devicesensing responses may be saved. In such an aspect, the set of saveddevice sensing responses may generate a history of potentiallyprogressively less ambiguous device sensing responses. Further, in suchan aspect, the history may be analyzed to determine one or more otherremote NFC devices within the operating volume. After the most recentlyreceived device sensing response has been received, the process mayreturn to block 508 for another iteration of collision resolution to beperformed.

While referencing FIG. 3, but turning also now to FIG. 6, an examplearchitecture of communications device 600 is illustrated. As depicted inFIG. 6, communications device 600 comprises receiver 602 that receives asignal from, for instance, a receive antenna (not shown), performstypical actions on (e.g., filters, amplifies, downconverts, etc.) thereceived signal, and digitizes the conditioned signal to obtain samples.Receiver 602 can comprise a demodulator 604 that can demodulate receivedsymbols and provide them to processor 606 for channel estimation.Processor 606 can be a processor dedicated to analyzing informationreceived by receiver 602 and/or generating information for transmissionby transmitter 620, a processor that controls one or more components ofcommunications device 600, and/or a processor that both analyzesinformation received by receiver 602, generates information fortransmission by transmitter 620, and controls one or more components ofcommunications device 600. Further, signals may be prepared fortransmission by transmitter 620 through modulator 618 which may modulatethe signals processed by processor 606.

Communications device 600 can additionally comprise memory 608 that isoperatively coupled to various components, such as but not limitedprocessor 606 and that can store data to be transmitted, received data,information related to available channels, TCP flows, data associatedwith analyzed signal and/or interference strength, information relatedto an assigned channel, power, rate, or the like, and any other suitableinformation for assisting in NFC peer mode connection establishment. Inan aspect, memory 608 may include an initially stored device sensingresponse 610. In an aspect, memory may further include one or moresubsequently received device sensing responses 612.

In an optional aspect, memory 608 may further store each received devicesensing response in a device sensing response storage structure 614(e.g., a table, matrix, etc.). In such an optional aspect, NFCtechnology detection module 660 may be configured to analyzing thestorage structure 614 after collision resolution is complete to identifyexact device sensing response values for each device. For example, aftercollision resolution is preformed for all remote NFC devices in anoperating volume, storage structure 614 may include example values asprovided in Table 1.

TABLE 1 Example SENS_RESs stored during Collision Resolution SENS_RES[0]000*0000 00001*00 SENS_RES[1] 00000000 00001*00 SENS_RES[2] 0000000000001100

In Table 1, a “*” indicates a bit location that experienced a collision.Continuing the above optional aspect, a cleaner device sensing response(SENS_RES[1]) may be inferred from the last device sensing response(SENS_RES[2]). Because SENS_RES[2] has a “1” value at the only collisionbyte location in SENS_RES[1], it can be inferred that the bit value is a“0” for SENS_RES[1]. Similarly, because SENS_RES[1] includes a “0” asthe fourth bit, it can be inferred that the bit value is “1” forSENS_RES[0]. As such, cleaner device sensing responses may be inferredfor each device through analysis of storage structure 614.

Further, processor 606, receiver 602, transmitter 620, device host 634,NFCC 630, and/or NFC technology detection module 660 can provide meansfor determining that a first device sensing response message includesone or more collisions among a plurality of remote NFC devices, meansfor identifying a first remote NFC device of the plurality of remote NFCdevices by performing collision resolution on the first device sensingresponse message, means for transmitting a sleep request message to thefirst remote NFC device that prohibits the first remote NFC device fromresponding to a first device sensing request message, means fortransmitting the first device sensing request message, means forreceiving a second device sensing response message that includescollisions among the plurality of remote NFC devices, and means foridentifying a second remote NFC device of the plurality of remote NFCdevices by performing collision resolution on the second device sensingresponse message.

It will be appreciated that data store (e.g., memory 608) describedherein can be either volatile memory or nonvolatile memory, or caninclude both volatile and nonvolatile memory. By way of illustration,and not limitation, nonvolatile memory can include read only memory(ROM), programmable ROM (PROM), electrically programmable ROM (EPROM),electrically erasable PROM (EEPROM), or flash memory. Volatile memorycan include random access memory (RAM), which acts as external cachememory. By way of illustration and not limitation, RAM is available inmany forms such as synchronous RAM (SRAM), dynamic RAM (DRAM),synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhancedSDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and direct Rambus RAM (DRRAM).Memory 608 of the subject systems and methods may comprise, withoutbeing limited to, these and any other suitable types of memory. In anaspect, memory 608 may further include one or more received devicesensing responses (SENS_RES) received as part of a collision resolutionprocess. In an aspect, an initially received device sensing response 610may be overwritten/replaced by a subsequent device sensing response 612.In another aspect, one or more subsequently received device sensingresponses 612 may be stored with the initially received device sensingresponse 610.

Communications device 600 may include a NFC controller 630 and devicehost 634. In an aspect, NFCC 630 may include RF discovery module 632. RFdiscovery module 632 may be configured to perform a discovery process.One aspect of the discovery process may include polling for the presenceof one or more remote NFC devices configured to communicate using aNFC-A RF technology. DH 634 may be configured to generate a command toprompt NFCC 630 to perform various functions associated with RFdiscovery.

In another aspect, communications device 600 may include NCI 650. In anaspect, NCI 650 may be configured to enable communications between a NFCenabled antenna (e.g., 602, 620), NFC controller 630 and DH 634. NCI 650may be configured to function in a listening mode and/or a polling mode.

In another aspect, communications device 600 may include NFC technologydetection module 660. NFC technology detection module 660 may beconfigured to generate and communicate a device sensing request message662. In an aspect, the device sensing request message 662 may be aSENS_REQ message as defined in the NFC Forum Digital Protocolspecification. NFC technology detection module 660 may receive one ormore device sensing response messages from one or more remote NFCdevices resulting in a received device sensing response that includesone or more collisions 664. In an aspect, each device sensing responsemessage may be a SENS_RES message as defined in the NFC Forum DigitalProtocol specification. NFC technology detection module 660 may furtherinclude collision resolution module 666 that may be configured toanalyze the received device sensing response that includes one or morecollisions 664. Although FIG. 6 detects NFC technology detection module660 is a separate module, one of ordinary skill in the art wouldappreciate that the functionality associated with NFC technologydetection module 660 may be included within one or more components, suchas but not limited to, NFCC 630, DH 634, etc. In another aspect, NFCtechnology detection module 660 configured to perform NFC technologydetection processes described with respect to FIGS. 4-5.

Additionally, communications device 600 may include user interface 640.User interface 640 may include input mechanisms 642 for generatinginputs into communications device 600, and output mechanism 644 forgenerating information for consumption by the user of the communicationsdevice 600. For example, input mechanism 642 may include a mechanismsuch as a key or keyboard, a mouse, a touch-screen display, amicrophone, etc. Further, for example, output mechanism 644 may includea display, an audio speaker, a haptic feedback mechanism, a PersonalArea Network (PAN) transceiver etc. In the illustrated aspects, theoutput mechanism 644 may include a display configured to present mediacontent that is in image or video format or an audio speaker to presentmedia content that is in an audio format.

FIG. 7 depicts another depicts a block diagram of an exemplarycommunication system 700 configured to improve technology detection andcollision resolution among multiple NFC devices using a NFC type-A RFtechnology, according to an aspect. For example, system 700 can resideat least partially within a communications device (e.g., communicationsdevice 600). It is to be appreciated that system 700 is represented asincluding functional blocks, which can be functional blocks thatrepresent functions implemented by a processor, software, or combinationthereof (e.g., firmware). System 700 includes a logical grouping 702 ofelectrical components that can act in conjunction.

For instance, logical grouping 702 can include an electrical componentthat may provide means for receiving a device sensing response messagethat may include collisions among a plurality of remote NFC devices 704.For example, in an aspect, the means for receiving 704 can includereceiver 602, DH 634, NFCC 630, NFC technology detection module 660,and/or processor 606 of communications device 600. In an aspect, themeans for receiving 704 may be configured to receive a first devicesensing response message in response. In an aspect, the means forreceiving 704 may be configured to receive a second device sensingresponse message that includes collisions among the plurality of remoteNFC devices. In an aspect, the means for receiving 704 may be configuredto receive a collision free device sensing response message. In anaspect, the means for receiving 704 may be configured to receive one ormore messages as part of single device detection communications. In anaspect, the device sensing response messages may be SENS_RES messages asdefined in the NFC Forum Digital Protocol specification. In anotheraspect, each of the plurality of remote NFC devices may be configured touse NFC-A RF technology. In another aspect, the remote NFC devices maybe a reader device, a writer device, a tag, a card, and a peer device,etc.

Further, logical grouping 702 can include an electrical component thatmay provide means for determining that a device sensing response messageincludes one or more collisions among a plurality of remote NFC devices706. For example, in an aspect, the means for determining 706 caninclude DH 634, NFCC 630, NFC technology detection module 660, and/orprocessor 606 of communications device 600.

Further, logical grouping 702 can include an electrical component thatmay provide means for identifying a remote NFC device by performingcollision resolution on the device sensing response message 708. Forexample, in an aspect, the means for identifying 708 can include DH 634,NFCC 630, NFC technology detection module 660, and/or processor 606 ofcommunications device 600. In an aspect, the means for identifying 708may be configured to identify a first remote NFC device of the pluralityof remote NFC devices by performing collision resolution on a firstdevice sensing response message. In an aspect, the means for identifying708 may be configured to identify a second remote NFC device of theplurality of remote NFC devices by performing collision resolution on asecond device sensing response message.

Moreover, logical grouping 702 can include an electrical component thatmay provide means for transmitting sleep request messages to identifiedremote NFC devices and/or device sensing request messages 710. Forexample, in an aspect, the means for transmitting 710 can includetransmitter 620, DH 634, NFCC 630, NFC technology detection module 660,and/or processor 606 of communications device 600. In an aspect, themeans for transmitting 710 may be configured to transmit a sleep requestmessage to an identified remote NFC device. In an aspect, the means fortransmitting 710 may be configured to transmit a first device sensingrequest message as part of a technology detection process. In an aspect,the means for transmitting 710 may be configured to transmit a seconddevice sensing request message. In an aspect, the means for transmitting710 may be configured to transmit one or more messages as part of singledevice detection communications. In an aspect, the sensing requestmessage may be a SENS_REQ message as defined in the NFC Forum DigitalProtocol specification. In another aspect, the sleep request message maybe a SLP_REQ message as defined in the NFC Forum Digital Protocolspecification.

In an optional aspect, logical grouping 702 can include an electricalcomponent that may provide means for storing device sensing responsemessages in a storage structure 712. For example, in an aspect, themeans for storing 712 can include memory 608 of communications device600. In an aspect, the means for storing 712 may be configured to storea first device sensing response message in a first location in a storagestructure. In an aspect, the means for storing 712 may be configured tostore a second device sensing response message in a second location inthe storage structure. In an aspect, the means for storing 712 may beconfigured to overwrite the first device sensing response message withthe second device sensing response message.

In another optional aspect, logical grouping 702 can include anelectrical component that may provide means for determining collisionfree versions of the first and second device sensing response messagesby analyzing the storage structure using the received collision freedevice sensing response message 714. For example, in an aspect, themeans for determining 714 can include DH 634, NFCC 630, NFC technologydetection module 660, and/or processor 606 of communications device 600.

Additionally, system 700 can include a memory 716 that retainsinstructions for executing functions associated with the electricalcomponents 704, 706, 708, 710, 712, and 714, stores data used orobtained by the electrical components 704, 706, 708, 710, 712, 714, etc.While shown as being external to memory 716, it is to be understood thatone or more of the electrical components 704, 706, 708, 710, 712, and714 may exist within memory 716. In one example, electrical components704, 706, 708, 710, 712, and 714 can include at least one processor, oreach electrical component 704, 706, 708, 710, 712, and 714 can be acorresponding module of at least one processor. Moreover, in anadditional or alternative example, electrical components 704, 706, 708,710, 712, and 714 may be a computer program product including a computerreadable medium, where each electrical component 704, 706, 708, 710,712, and 714 may be corresponding code. In an aspect, for example,memory 716 may be the same as or similar to memory 608 (FIG. 6). Inanother aspect, memory 716 may be associated with DH 634, NFCC 630,and/or NFC technology detection module 660.

As used in this application, the terms “component,” “module,” “system”and the like are intended to include a computer-related entity, such asbut not limited to hardware, firmware, a combination of hardware andsoftware, software, or software in execution. For example, a componentmay be, but is not limited to being, a process running on a processor, aprocessor, an object, an executable, a thread of execution, a program,and/or a computer. By way of illustration, both an application runningon a computing device and the computing device can be a component. Oneor more components can reside within a process and/or thread ofexecution and a component may be localized on one computer and/ordistributed between two or more computers. In addition, these componentscan execute from various computer readable media having various datastructures stored thereon. The components may communicate by way oflocal and/or remote processes such as in accordance with a signal havingone or more data packets, such as data from one component interactingwith another component in a local system, distributed system, and/oracross a network such as the Internet with other systems by way of thesignal.

Furthermore, various aspects are described herein in connection with aterminal, which can be a wired terminal or a wireless terminal Aterminal can also be called a system, device, subscriber unit,subscriber station, mobile station, mobile, mobile device, remotestation, mobile equipment (ME), remote terminal, access terminal, userterminal, terminal, communication device, user agent, user device, oruser equipment (UE). A wireless terminal may be a cellular telephone, asatellite phone, a cordless telephone, a Session Initiation Protocol(SIP) phone, a wireless local loop (WLL) station, a personal digitalassistant (PDA), a handheld device having wireless connectioncapability, a computing device, or other processing devices connected toa wireless modem. Moreover, various aspects are described herein inconnection with a base station. A base station may be utilized forcommunicating with wireless terminal(s) and may also be referred to asan access point, a Node B, or some other terminology.

Moreover, the term “or” is intended to mean an inclusive “or” ratherthan an exclusive “or.” That is, unless specified otherwise, or clearfrom the context, the phrase “X employs A or B” is intended to mean anyof the natural inclusive permutations. That is, the phrase “X employs Aor B” is satisfied by any of the following instances: X employs A; Xemploys B; or X employs both A and B. In addition, the articles “a” and“an” as used in this application and the appended claims shouldgenerally be construed to mean “one or more” unless specified otherwiseor clear from the context to be directed to a singular form.

The techniques described herein may be used for various wirelesscommunication systems such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA and othersystems. The terms “system” and “network” are often usedinterchangeably. A CDMA system may implement a radio technology such asUniversal Terrestrial Radio Access (UTRA), cdma2000, etc. UTRA includesWideband-CDMA (W-CDMA) and other variants of CDMA. Further, cdma2000covers IS-2000, IS-95 and IS-856 standards. A TDMA system may implementa radio technology such as Global System for Mobile Communications(GSM). An OFDMA system may implement a radio technology such as EvolvedUTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE802.16 (WiMAX), IEEE 802.20, Flash-OFDMA, etc. UTRA and E-UTRA are partof Universal Mobile Telecommunication System (UMTS). 3GPP Long TermEvolution (LTE) is a release of UMTS that uses E-UTRA, which employsOFDMA on the downlink and SC-FDMA on the uplink. UTRA, E-UTRA, UMTS, LTEand GSM are described in documents from an organization named “3rdGeneration Partnership Project” (3GPP). Additionally, cdma2000 and UMBare described in documents from an organization named “3rd GenerationPartnership Project 2” (3GPP2). Further, such wireless communicationsystems may additionally include peer-to-peer (e.g., mobile-to-mobile)ad hoc network systems often using unpaired unlicensed spectrums, 802.xxwireless LAN, BLUETOOTH, near-field communications (NFC-A, NFC-B,NFC,-f, etc.), and any other short- or long-range, wirelesscommunication techniques.

Various aspects or features will be presented in terms of systems thatmay include a number of devices, components, modules, and the like. Itis to be understood and appreciated that the various systems may includeadditional devices, components, modules, etc. and/or may not include allof the devices, components, modules etc. discussed in connection withthe figures. A combination of these approaches may also be used.

The various illustrative logics, logical blocks, modules, and circuitsdescribed in connection with the aspects disclosed herein may beimplemented or performed with a general purpose processor, a digitalsignal processor (DSP), an application specific integrated circuit(ASIC), a field programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general-purpose processor may be a microprocessor,but, in the alternative, the processor may be any conventionalprocessor, controller, microcontroller, or state machine. A processormay also be implemented as a combination of computing devices, e.g., acombination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration. Additionally, at least oneprocessor may comprise one or more modules configured to perform one ormore of the steps and/or actions described above.

Further, the steps and/or actions of a method or algorithm described inconnection with the aspects disclosed herein may be embodied directly inhardware, in a software module executed by a processor, or in acombination of the two. A software module may reside in RAM memory,flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a harddisk, a removable disk, a CD-ROM, or any other form of storage mediumknown in the art. An example storage medium may be coupled to theprocessor, such that the processor can read information from, and writeinformation to, the storage medium. In the alternative, the storagemedium may be integral to the processor. Further, in some aspects, theprocessor and the storage medium may reside in an ASIC. Additionally,the ASIC may reside in a user terminal. In the alternative, theprocessor and the storage medium may reside as discrete components in auser terminal Additionally, in some aspects, the steps and/or actions ofa method or algorithm may reside as one or any combination or set ofcodes and/or instructions on a machine readable medium and/or computerreadable medium, which may be incorporated into a computer programproduct.

In one or more aspects, the functions described may be implemented inhardware, software, firmware, or any combination thereof. If implementedin software, the functions may be stored or transmitted as one or moreinstructions or code on a computer-readable medium. Computer-readablemedia includes both computer storage media and communication mediaincluding any medium that facilitates transfer of a computer programfrom one place to another. A storage medium may be any available mediathat can be accessed by a computer. By way of example, and notlimitation, such computer-readable media can comprise RAM, ROM, EEPROM,CD-ROM or other optical disk storage, magnetic disk storage or othermagnetic storage devices, or any other medium that can be used to carryor store desired program code in the form of instructions or datastructures and that can be accessed by a computer. Also, any connectionmay be termed a computer-readable medium. For example, if software istransmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,includes compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and blu-ray disc where disks usually reproducedata magnetically, while discs usually reproduce data optically withlasers. Combinations of the above should also be included within thescope of computer-readable media.

While the foregoing disclosure discusses illustrative aspects and/oraspects, it should be noted that various changes and modifications couldbe made herein without departing from the scope of the described aspectsand/or aspects as defined by the appended claims. Furthermore, althoughelements of the described aspects and/or aspects may be described orclaimed in the singular, the plural is contemplated unless limitation tothe singular is explicitly stated. Additionally, all or a portion of anyaspect and/or aspect may be utilized with all or a portion of any otheraspect and/or aspect, unless stated otherwise.

What is claimed is:
 1. A method of wireless communications, comprising:determining that a first device sensing response message includes one ormore collisions among a plurality of remote near field communication(NFC) devices; identifying a first remote NFC device of the plurality ofremote NFC devices by performing collision resolution on the firstdevice sensing response message; transmitting a sleep request message tothe first remote NFC device, which causes the first remote NFC device totransition to a sleep state that prohibits the first remote NFC devicefrom responding to a first device sensing request message; transmittingthe first device sensing request message; receiving a second devicesensing response message that includes collisions among the plurality ofremote NFC devices; identifying a second remote NFC device of theplurality of remote NFC devices by performing collision resolution onthe second device sensing response message; storing the first devicesensing response message in a first location in a storage structure, andthe second device sensing response message in a second location in thestorage structure; receiving a collision free device sensing responsemessage; and determining collision free versions of the first and seconddevice sensing response messages by analyzing the first device sensingresponse message in the first location and the second device sensingresponse message in the second location in the storage structure usingthe received collision free device sensing response message.
 2. Themethod of claim 1, further comprising: transmitting a second devicesensing request message as part of a technology detection process; andreceiving the first device sensing response message in response to thesecond device sensing request message.
 3. The method of claim 1, whereinthe second device sensing response message overwrites the first devicesensing response message.
 4. The method of claim 1, wherein each of theplurality of remote NFC devices is configured to use NFC-A radiofrequency (RF) technology.
 5. The method of claim 1, wherein the firstand second device sensing response messages are SENS_RES messages asdefined in the NFC Forum Digital Protocol specification.
 6. The methodof claim 1, wherein the second device sensing request message is aSENS_REQ message as defined in the NFC Forum Digital Protocolspecification.
 7. The method of claim 1, wherein the sleep requestmessage is a SLP_REQ message as defined in the NFC Forum DigitalProtocol specification.
 8. The method of claim 1, wherein the pluralityof remote NFC devices comprise at least one of a reader device, a writerdevice, a tag, a card, and a peer device.
 9. The method of claim 1,further comprising performing single device detection communicationswith each device that transmitted a device sensing response message toobtain a NFC device identifier (NFCID).
 10. A non-transitorycomputer-readable medium, storing computer-executable code for wirelesscommunications, comprising: code for determining that a first devicesensing response message includes one or more collisions among aplurality of remote near field communication (NFC) devices; code foridentifying a first remote NFC device of the plurality of remote NFCdevices by performing collision resolution on the first device sensingresponse message; code for transmitting a sleep request message to thefirst remote NFC device, which causes the first remote NFC device totransition to a sleep state that prohibits the first remote NFC devicefrom responding to a first device sensing request message; code fortransmitting the first device sensing request message; code forreceiving a second device sensing response message that includescollisions among the plurality of remote NFC devices; code foridentifying a second remote NFC device of the plurality of remote NFCdevices by performing collision resolution on the second device sensingresponse message; code for storing the first device sensing responsemessage in a first location in a storage structure, and the seconddevice sensing response message in a second location in the storagestructure; code for receiving a collision free device sensing responsemessage; and code for determining collision free versions of the firstand second device sensing response messages by analyzing the firstdevice sensing response message in the first location and the seconddevice sensing response message in the second location in the storagestructure using the received collision free device sensing responsemessage.
 11. The non-transitory computer-readable medium of claim 10,further comprising: code for transmitting a second device sensingrequest message as part of a technology detection process; and code forreceiving the first device sensing response message in response to thesecond device sensing request message.
 12. The non-transitorycomputer-readable medium of claim 10, wherein the second device sensingresponse message overwrites the first device sensing response message.13. The non-transitory computer-readable medium of claim 10, whereineach of the plurality of remote NFC devices is configured to use NFC-Aradio frequency (RF) technology.
 14. The non-transitorycomputer-readable medium of claim 10, wherein the first and seconddevice sensing response messages are SENS_RES messages as defined in theNFC Forum Digital Protocol specification.
 15. The non-transitorycomputer-readable medium of claim 10, wherein the second device sensingrequest message is a SENS_REQ message as defined in the NFC ForumDigital Protocol specification.
 16. The non-transitory computer-readablemedium of claim 10, wherein the sleep request message is a SLP_REQmessage as defined in the NFC Forum Digital Protocol specification. 17.The non-transitory computer-readable medium of claim 10, wherein theplurality of remote NFC devices comprise at least one of a readerdevice, a writer device, a tag, a card, and a peer device.
 18. Thenon-transitory computer-readable medium of claim 10, wherein thenon-transitory computer-readable medium further comprises code forperforming single device detection communications with each device thattransmitted a device sensing response message to obtain a NFC deviceidentifier (NFCID).
 19. An apparatus for communications, comprising:means for determining that a first device sensing response messageincludes one or more collisions among a plurality of remote near fieldcommunication (NFC) devices; means for identifying a first remote NFCdevice of the plurality of remote NFC devices by performing collisionresolution on the first device sensing response message; means fortransmitting a sleep request message to the first remote NFC device,which causes the first remote NFC device to transition to a sleep statethat prohibits the first remote NFC device from responding to a firstdevice sensing request message; wherein the means for transmitting isfurther configured to transmit the first device sensing request message;means for receiving a second device sensing response message thatincludes collisions among the plurality of remote NFC devices; whereinthe means for identifying is further configured to identify a secondremote NFC device of the plurality of remote NFC devices by performingcollision resolution on the second device sensing response message;means for storing the first device sensing response message in a firstlocation in a storage structure, and the second device sensing responsemessage in a second location in the storage structure; wherein the meansfor receiving is further configured to receive a collision free devicesensing response message; and means for determining collision freeversions of the first and second device sensing response messages byanalyzing the first device sensing response message in the firstlocation and the second device sensing response message in the secondlocation in the storage structure using the received collision freedevice sensing response message.
 20. The method of claim 19, wherein themeans for transmitting is further configured to transmit a second devicesensing request message as part of a technology detection process; andwherein the means for receiving is further configured to receive thefirst device sensing response message in response to the second devicesensing request message.
 21. The apparatus of claim 19, wherein thesecond device sensing response message overwrites the first devicesensing response message.
 22. The apparatus of claim 19, wherein each ofthe plurality of remote NFC devices is configured to use NFC-A radiofrequency (RF) technology.
 23. The apparatus of claim 19, wherein thefirst and second device sensing response messages are SENS_RES messagesas defined in the NFC Forum Digital Protocol specification.
 24. Theapparatus of claim 19, wherein the second device sensing request messageis a SENS_REQ message as defined in the NFC Forum Digital Protocolspecification.
 25. The apparatus of claim 19, wherein the sleep requestmessage is a SLP_REQ message as defined in the NFC Forum DigitalProtocol specification.
 26. The apparatus of claim 19, wherein theplurality of remote NFC devices comprise at least one of a readerdevice, a writer device, a tag, a card, and a peer device.
 27. Theapparatus of claim 19, wherein the means for receiving and means fortransmitting are further configured to perform single device detectioncommunications with each device that transmitted a device sensingresponse message to obtain a NFC device identifier (NFCID).
 28. Anapparatus for NFC communications, comprising: a transceiver; a memory; aprocessor coupled to the memory; and a NFC technology detection modulecoupled to at least one of the memory or the processor and configuredto: determine that a first device sensing response message includes oneor more collisions among a plurality of remote near field communication(NFC) devices; and identify a first remote NFC device of the pluralityof remote NFC devices by performing collision resolution on the firstdevice sensing response message; wherein the transceiver is configuredto: transmit a sleep request message to the first remote NFC device,which causes the first remote NFC device to transition to a sleep statethat prohibits the first remote NFC device from responding to a firstdevice sensing request message; transmit the first device sensingrequest message; receive a second device sensing response message thatincludes collisions among the plurality of remote NFC devices; andwherein the NFC technology detection module is further configured to:identify identifying a second remote NFC device of the plurality ofremote NFC devices by performing collision resolution on the seconddevice sensing response message; wherein the memory is furtherconfigured to store the first device sensing response message in a firstlocation in a storage structure, and the second device sensing responsemessage in a second location in the storage structure; wherein thetransceiver is further configured to receive a collision free devicesensing response message; and wherein the NFC technology detectionmodule is further configured to determine collision free versions of thefirst and second device sensing response messages by analyzing the firstdevice sensing response message in the first location and the seconddevice sensing response message in the second location in the storagestructure using the received collision free device sensing responsemessage.
 29. The apparatus of claim 28, wherein the transceiver isfurther configured to: transmit a second device sensing request messageas part of a technology detection process; and receive the first devicesensing response message in response to the second device sensingrequest message.
 30. The apparatus of claim 28, wherein the seconddevice sensing response message overwrites the first device sensingresponse message in the memory.
 31. The apparatus of claim 28, whereineach of the plurality of remote NFC devices is configured to use NFC-Aradio frequency (RF) technology.
 32. The apparatus of claim 28, whereinthe first and second device sensing response messages are SENS_RESmessages as defined in the NFC Forum Digital Protocol specification. 33.The apparatus of claim 28, wherein the second device sensing requestmessage is a SENS_REQ message as defined in the NFC Forum DigitalProtocol specification.
 34. The apparatus of claim 28, wherein the sleeprequest message is a SLP_REQ message as defined in the NFC Forum DigitalProtocol specification.
 35. The apparatus of claim 28, wherein theplurality of remote NFC devices comprise at least one of a readerdevice, a writer device, a tag, a card, and a peer device.
 36. Theapparatus of claim 28, wherein the NFC technology detection module isfurther configured to perform single device detection communicationswith each device that transmitted a device sensing response message toobtain a NFC device identifier (NFCID).